Speed governor



April 9- G. \i'oN ARCO 1,708,529

SPEED GOVERNOR Filed June 28, 1 924 7 GEORG VON ARCO INVENTOR ATTORNEY Patented Apr. 9, 1929.

UNITED STATES ome I GEORG- VON ARGO, OF BERLIN, GERMANY, ASSIGNOR TO GESELLSCHAFT FOR BRAKE.- I LOSE TELEGRAPHIE M. B. 1-1., OF BERLIN, S. W. 11, GERMANY, A CORPORATION OF GERMANY.

Application filed June 28, 1924, Serial No. 723,064, and in Germany July 2, 1923.

My invention relates to means for automatically maintaining the speed of a rotating machine approximately constant. It has for its object to provide a governor which will be very sensitive to speed variat on and keep the speed within very narrow limits as this is particularly desirable in high speed alternators such as used in radio.

Other objects will be apparent to those skilled in the art from the following specification and claims when considered with the micompanying drawing, in which the single figure represents an embodiment of my invention.

The arrangement described in the following is known as a governor of the speed of rotation of a machine.

A mechanical system consisting o t a spring and a weight is arranged on a turn-table, rotating about a horizontal axis in such a way that the centrifugal force of the mass is balanced by the force of the spring for a certain critical speed of rotation. For this speed the mechanical oscillating system is in an unstable equilibrium. The equilibrium between mass and spring is disturbed by the slightest alteration ofthe speed and the centrifugal force.

The force of gravity is added to and subtracted from the centrifugal force at every revolution, so that the mass carries out an oscillation of a certain amplitude at every revol ution j A. disadvantage of this very sensitive regulating system is that the mass as well as the force of the spring must be altered, if the condition of unstable equilibrium is to be newly adjusted for another desired speed of rotation. It is very difficult in practice to alter the critical speed of rotation by adj usting the governor itself. 'lhoret'ore, it is remedied by driving the governor thru variable gearing by the machine, the speed of which is to be controlled.

The purpose of an invention disclosed in German application T. 27,816 1/60 and in United States application S. N. 716,532 filed May 29, 1924, was to remove this ditliculty by regulating the governor itself. The principle of the invention was that the whole mass of the oscillating system is divided into two parts, one of which is subjected to the centrifugal force and the other not. Therefore, this second part can be made larger act alone. This case occurs, for instance, if

the axis of revolution of the governor is vertical.

The invention will be better understood from the following description taken in connection with the drawing in which:

Fig. 1 is a plan view of the governor.

The drawing shows the invention in its Simplest form and diagrammatically. Two spring plates B, and 13 one of which is adapted to coact with a terminal 0, are mounted on the turntable A, which. in turn. may be mounted on an horizontal or vertical axis which is operatively connected to the rotating element of the machine it is desirad to govern. The two spring-plates are connected by the rod 1) and the weight F is arranged in the iniddlobf the rod, exactly in the axis of revolution.

The resilience of the spring-plates B, and B between the places where they are fixed to the turntable A and the places where the rod D is fixed, suppliesthe spring action necessary to resist the centrifugal force of mass E. Terminal C is also mounted on turntable A. Contact is made and broken between terminal C and spring-plate R for different periods of time depending on the speed of rotation as will be pointed out below more in detail. The making and breaking of this contact serves to operate any wellknown devices for regulating the-speed of the machine and may also serve to operate a device (not shown) for stopping the machine if the speed becomes either abnormally high or low.

The additional weight E, smaller than F. is mounted on rod 1) between plate B and weight F. Weight 1:" exeits just enough centrifugal force when the machine is running at the desired speed to balance the force exerted by spring-plates B and B When the machine is running under this condition contact between late B and terminal C will be open and closed every revolution due to the force of the artificial field and the force of gravity on mass F and mass E if the axis of revolution of the governor is horizontal, and due to the force of the artificial field alone if the axis ofrevolution is vertical.

The artificial field may be due to an electromagnet M arrangedso as to exert force on the governor principally upon the masses E and F which will be made of magnetic material. The battery G and rlieostat H is provided to vary the magnetic force exerted by the magnet upon the masses E and F. The chief advantage of this improvement is that by adjusting the amount of current thru the winding of the magnet M, the strength of the field is also adjusted and it is thereby possible to adjust the sensitivencss and range vof regulation of the governor while the machine is running.

It is also possible to use, not a constant field, but a field which is periodically altered in accordance with the frequency or corresponding speed of rotation.

Thus it will easily be seen that if the machine speeds up above desired speed the centrifugal force of weight E will overcome the spring action of plates B and B and the contact between plate B and terminal C will remain closed longer than when running at desired speed. On the other hand, if the machine speed decreases from desired speed, the spring action of spring-plates B and B will overcome the centrifugal force of weight E and the contact between plate B and terminal C will remain open longer than when running at desired speed.

It will easil be seen by those skilled in the art that cliange of relative periods of open and closed position of the contacts can control the speed of the machine in conjunction with any of the well-known devices in the art.

Having disclosed the principle of my invention, various modifications will beapparent to those skilled in the art. My invention, therefore, is not limited to the specific disclosure, but only by the scope of the following claims? 1. A speed control device comprising a rotatable member, a radial member resiliently mounted on said rotatable member, centrifugal means associated with said radial member for making and breaking an electrical circuit, and variable magnetic means to alternately aid and oppose the action of said centrifugal means.

2. A speed-control device comprising a rotatable member, a radial member resiliently mounted on said first mentioned member, means governed by the speed of rotation of the rotatable member to close an electrical circuit, and variable ma netic means to alternately aid and oppose t e action of said last mentioned means.

3. A speed control device comprising a rotatable member, a radial member resiliently mounted on said rotatable member, centrifugal means associated with said radial member for making and breaking an electrical circuit, and magnetic means to alternately and variably aid and oppose the action of said centrifugal means.

4. The arrangement for controlling the speed of a rotary machine by the relative length of the closed and open periods in a \circuit, comprising a rotary member attached to said machine and adapted to rotate therewith, a magnetic mass resiliently mounted on said member and adapted to oscillate relative thereto, contacts adapted to be closed by the oscillation of said mass and stationary variable magnetic means for affecting the magnetic mass and altering the relative length of the open and closed pcriods of said contacts.

GEORG VON ARGO. 

